For many years it has been customary to feed cards (carding machines) from laps of fibers, which have been formed, for example, by a picker machine or the like. To accomplish this, manpower and diverse machinery have been employed to transfer the laps from the pickers to the cards. Generally, a lap of fibers unrolls with a web of fairly uniform density and thickness, and consequently is quite suitable for feeding into a card. More recently, however, efforts have been made to obviate the necessity of forming a lap and transporting it from a picker to the card which is to use it. With the advent of efficient pneumatic conveying systems, especially condensers for removing fibers from the air stream and supplying them to equipment, it has become easier to supply fibers directly to cards. A web of fibers has been fed directly to a card, other than by a lap, in the required density and thickness uniformity with various types of regulating devices which have been generally known by various terms such as chute feeds, feeding regulators, web formers and the like. These web formers have been used in various manners, such as receiving the previously opened fibers directly from a condenser in a pneumatic conveyor system. In addition, web formers have been employed as the output equipment of opening and feeding hoppers.
When a chute feeder is juxtaposed upstream of a card as a web supply means therefor, often a single motor means is used to drive both devices, with suitable drive belt and sprocket means operatively interconnecting the two devices. Such a combination of equipment is illustrated in FIG. 2 of the U.S. Pat. No. 3,750,235, of Wise, issued Aug. 7, 1973. In the instance depicted, in this Wise patent, the chute feeder is shown resting on the floor in simple juxtaposition with the card. In other instances, the chute feeder may be physically supported upon an upstream end portion of the frame of the card. Such an arrangement is depicted in FIG. 1 of the U.S. Pat. No. 4,009,803, of K. G. Lytton et al, issued Mar. 1, 1977. In other instances, the chute feeder may be supported upon some other item of equipment or on a pedestal, stand or the like.
Quite usually a third item of textile processing equipment, a coiler, is juxtaposed downstream of a card, so that the output web of the card is coiled into a can. In the U.S. Pat. No. 4,154,485, of K. G. Lytton et al, issued May 15, 1979 a plurality of such three-part units are shown connected in a system to be operated in parallel, with a manifold supplying fibers to the chute feeders of all the units. In a modern "dual coiler" variation, two coilers are positioned side-by-side at the front of the card. In using such an arrangement, the output web of the card is split longitudinally into a left portion which is developed by the left coiler as a sliver coilingly fed into the left can, and into a right portion which is developed by the right coiler as a sliver coilingly fed into the right can.
Typically, when a chute feeder is mated with a card, the chute feeder is selected so as to provide as output a batt that is somewhat narrower than the maximum width which could be accepted by the card, e.g. a thirty-six inch wide feed for a forty inch card, this to accommodate some migration without causing migration onto the sides of the card.
Particularly as cards are run at faster speeds to process more weight of fiber per unit time, uniformity of the output, especially for a dual coiler, has become a problem, both due to variations within the feed to each coiler and variations between the feeds to the coilers.
The present invention has determined that a substantial proportion of the variability results from improper juxtaposition of the chute feeder with the card, particularly as to relative lateral positioning. Although it might be possible to reduce the variability by shifting the entire card slightly to the left or to the right relative to the chute feeder, or vice versa, such an adjustment is considered impractical due to consequential disruption of piping connections and the like.